Safety-envelop.



T. HOPFMANN.

SAFETY BNVELOP.

APPLICATION FILED AUG. 5, 1912.

1,0 1 ,07'7, Patented May 6,- 1913.

5 U ED STATES PATEN our ou FERDINAND HOFFMANN, on sat Louis, mssounr.

SAFETY-ENVEI-(li.

Specification of Letters Pate tt.

Patented May 6, 1913.

Application filed August 5, 1912. Serial No. 713,402.-

To all whom it may concern:

Be it known that I, FERDINAND Horr- MANN, a citizen of the United States, and residentof'St. Louis, Missouri, have invented certain new and useful Improvements in Safety-Envelops, of which the following is a specification, containing a full, clear, and

exact description, reference being had tothe accompanying drawings, forming a part hereof. v

My invention relates to improvements in I safety envelops, and the object of my'inven- -'tion is to construct an improved safety envelop which cannotbe opened, after having :of the bottom flap being broken away; Fig.

3 is a rear elevation of one of my improved envelops 1n a sealed condition; Fig. 4 1s a transverse, sectional elevation taken on the line 44 of .Fig. 2; and Fig. 5 is a trans verse, sectional elevation taken on the line 5. 5 of Fig. a.

Referring by numerals to the accompanying drawings: 6 designates the .body portion or front. of the envelop and, as shown, this body portion is substantially rectangular.

7 designates the bottom flap which is substantially triangular-shaped with one of its marginsintegral with the front 6 and its two free margins provided with gummed lines 8. Adjacent the apex of the bottom flap 7 there is a slot 9 one edge of which is straight so that it parallels the 'major axis of the front 6, the surface of the flap 7, between said slot andthe apex of the flap, being gummed. 1 i

10 and 11 designate the side flaps which are substantially triangular-shaped and have their one margin formed integral with the front 6. Formed integral with each of the side flaps is an extension 12, each of which extensions carries a detector-strip 13. l4 designates a sealing flap which is substantiallytriangular-shaped and hzt ifione of its margins formed integral with e front the tearing cuts 18.

e. Adjacent the apex of the;.-sealing flag 14 there are tearing notches 15 between w ich is located a tongue 16, the widthof which is substantially the same as the length of the slot 9'in the bottom flap. 4 v

17, designates a gummed line adjacent the entire free margin of the flap 14 and including the tongue 16.

Formed in the 'sealin flap 14 parallel with the minor axis of t e envelop andr extended into the flap rom the notches 15 are In forming an envelop from one blanks, as shown in Fig. 1, 1t 1s nece ary only to ld the side flaps 10 and 11 arallel with thefront 6, the gummed lines of the bottomflap are then moistened and the bottom flap folded parallel with the front 6,-

so that the gummed lines 8 will adhere to the margins of thesaid side flaps 10 and 11.-

In this manner the detector strips 13 occupy a position paralleling the minor axis of the envelop and aline with the slot "9 in the bottom flap. To seal the envelop, it is necessary only to moisten the gummed surface 17 of the sealing flap. The tongue, after being moistened, is then inserted through-- the slot- 9 and will be adhered to the exten sion 12 and the detector strips 13, the remainder of the gummed surface of the sealing flap will adhere to the bottom flap surrounding the slot 9 and to the side flaps 10 and 11. v

For the reason that a portion of the sealing flap is located beneath the bottom flap it is impossible to open the envelop, Without detection, by means of a blade which would be placed between the sealing flap and the envelop proper. Any attempts toward .inserting an instrument between the sealing flap and the bodv would tend to separate the flap from the body portion, and thus tear the cuts 18 which would be readily noticed. If' steaming were resorted to to render the gum non-adhesive it is obvious; for the reason that a portion of the flap,

namely the'tongue,- is unexposed. the gum on the tongue would not be rendered nonadhesive by the steam, hence the gum upon the tongue would adhere to the detector strips '13 and, when moved, would tear said detector strips;

By reason of'the-fact that the sand slot- 9 has an exposed straight edge, the material thereof will'in use lie perfectly flat and W111 a t to more securely hold the tongue 'lo i position in said slot, the straig lit edge of said. slot holding the tongue securely in-po-' sition; the'gends of saidslot also act as guidesto limit t'he late 'al movement of the:

tongue.

The envelop of my improved .constnuction nearthe apex of the flap, there being a single straight-edged longitudinal slot in said bot-i tom flapadjacent the apex thereof, a pair of side flaps, two integral detector-strips extending from the bottoms no increased expense carried by said side flaps which, when the 20 envelop is formed, saline with said slot, a sealing flap having two arallel tearingnotchesforined in the margin of the sealingflap'adja'cent its apex and two tearing-cuts of said notches, 25 and a gummed sealing tongue between said notches and adapted to be inserted in said slot to's'eal the abutting ends of said side flaps to' the said parallel detector-strips, the ends of said slot acting as guides to limit the lateral'mov'ement of said tongue.

In testimony whereof, I have signed my name to this specifioation in presence of two subscribing witnesses.

I FERDINAND HOFFi IANN.-

Witnesses: E. L. WALLACE, I

E. M. HARRINGTON. 

